Assessment of Residual Element Tolerance in Bearing Steels Produced from Recycled Obsolete Scrap via the Electric Arc Furnace (EAF) Process

About the project

About the Project The Nationally Determined Contribution (NDC) under the Paris Agreement aims to achieve net zero CO₂ emissions by 2050, with a key focus on high-impact sectors such as steel and transportation. Iron and steel accounts for approximately 8% of global CO₂. Using steel scrap instead of virgin ore can reduce emissions by up to 58% and water consumption by 40%. As shown in Fig. 1, the Electric Arc Furnace (EAF) route can employ 100% scrap recycling, compared to ~20% in the conventional BF-BOF route. With renewable electricity, EAF-based steelmaking can approach near-zero emissions, making it a key pathway for decarbonisation in the UK. In 2023, Tata Steel and the UK Government announced a £1.25 billion investment to replace blast furnaces at Port Talbot with a 3Mt EAF, alongside £300 million to support British Steel’s transition. The adoption of the EAF route for all steel grades is constrained by the challenge of residual elements such as Cu, and Sn from obsolete scrap, which significantly affect the mechanical properties of the final steel products. For example, higher levels of residual elements from steel scrap can lead to both micro- and macroscale issues, such as segregation and cracking, during the solidification and casting process. Cu has been reported to promote the formation of brittle intermetallic compounds at grain boundaries, leading to hot shortness and hot embrittlement through a Cu-rich liquid phase during hot working. In addition, Sn reduces the solubility of Cu in the austenite phase, which further exacerbates hot shortness and degrades impact toughness. Research on removing such elements from steel scrap dates back to the 1950s. Although some progress has been made, advancements remain largely at the laboratory scale. Consequently, the recycling of obsolete steel scrap often requires dilution with virgin iron to ensure compliance with the stringent residual element limits specified for various steel grades. To substantially increase the recycling rate of obsolete scrap and achieve significant reductions in carbon emissions and energy consumption via EAF steelmaking, it is crucial to enable direct recycling with less dilution. Consequently, there is an urgent need to expand the acceptable limits for residual element contents. This project addresses this challenge by focusing on bearing steels, which are widely used as high-quality, high-value materials in the aerospace, automotive, and renewable energy sectors. Bearing steels are considered ultra-clean steels, requiring extremely low levels of non-metallic inclusions to maximise fatigue life, making the tolerance of residual elements more restrictive than in many other steel grades. In addition, the complex heat treatment processes used to achieve specific phase fractions and tailored microstructures in bearing steels further complicate the influence of residual elements on microstructural evolution and component performance. The outcomes of this project will establish acceptable ranges for residual element contents and their corresponding manufacturing parameters. This will provide valuable guidance and technological strategies applicable to a wide range of steel grades, enabling the more effective recycling of obsolete scrap through the EAF route while supporting evolving industrial demands and environmental objectives. This project brings together a strong network of academic and industrial collaborators, including WMG, University of Warwick, Speciality Steel UK, Rolls-Royce, and SKF. Each partner contributes distinct expertise across the full steel development and application chain, ensuring both scientific depth and industrial relevance.The University of Manchester provides additional training opportunities for PhD students, such as research development, career services, and software training, to support their future career aspirations. The student will also be supported in attending conferences and workshops to present their work. Before you apply We strongly recommend that you contact the supervisors for this project before you apply. Please include details of your current level of study, academic background and any relevant experience and include a paragraph about your motivation to study this PhD project. How to apply Apply online through our website: https://uom.link/pgr-apply-2425 When applying, you’ll need to specify the full name of this project, the name of your supervisor, if you already having funding or if you wish to be considered for available funding through the university, details of your previous study, and names and contact details of two referees. Your application will not be processed without all of the required documents submitted at the time of application, and we cannot accept responsibility for late or missed deadlines. Incomplete applications will not be considered. After you have applied you will be asked to upload the following supporting documents: Final Transcript and certificates of all awarded university level qualifications Interim Transcript of any university level qualifications in progress CV Supporting statement: A one or two page statement outlining your motivation to pursue postgraduate research and why you want to undertake postgraduate research at Manchester, any relevant research or work experience, the key findings of your previous research experience, and techniques and skills you’ve developed. (This is mandatory for all applicants and the application will be put on hold without it). Contact details for two referees (please make sure that the contact email you provide is an official university/work email address as we may need to verify the reference) English Language certificate (if applicable) If you have any questions about making an application, please contact our admissions team by emailing FSE.doctoralacademy.admissions@manchester.ac.uk . Equality, diversity and inclusion is fundamental to the success of The University of Manchester, and is at the heart of all of our activities. We know that diversity strengthens our research community, leading to enhanced research creativity, productivity and quality, and societal and economic impact. We actively encourage applicants from diverse career paths and backgrounds and from all sections of the community, regardless of age, disability, ethnicity, gender, gender expression, sexual orientation and transgender status. We also support applications from those returning from a career break or other roles. We consider offering flexible study arrangements (including part-time: 50%, 60% or 80%, depending on the project/funder).

Research areas